Had the Flu? It Was Probably Swine Flu

Doctors across the nation are saying people who came down with the flu this summer probably had the new swine flu, also known as the H1N1 flu strain.

ABC News Photo Illustration

If you're wondering whether your sniffling co-worker's bout of flu is indeed the swine flu, then wonder no more.

Doctors across the nation are saying people who came down with the flu this summer probably had the new swine flu (H1N1) strain.

"In the U.S., all the flu that is circulating now is the H1N1 virus," said ABC News Senior Health and Medical Editor Dr. Richard Besser on "Good Morning America" Wednesday. "If you've had the flu; you've had the swine flu."

Since the U.S. Centers for Disease Control and Prevention first started tracking the H1N1 strain in mid-April, the agency has counted 9,079 hospitalizations because of it.

"What we're seeing in terms of illness is relatively mild. So unless you're in one of the high-risk groups, you can treat this with rest, fluids, chicken soup and staying away from other people to avoid spreading it to them. That, for the most part, is very effective," said Besser.

"Since there are no reports of mutation of the virus to a more lethal strain, the public should take comfort in the fact that in the overwhelming majority of cases (those people that are not high risk) this virus causes a relatively mild, self-limited illness," said Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City.

Reason Two: Swine Flu Survivors May Be Immune to Reinfection

With a few months of investigation under their belt, immunologists are saying that the swine flu comes with more good news: it appears people who get sick with swine flu may not become sick from the same strain again.

What's more, even people who were sick in the past with a slightly different virus may have some protection against the current strain.

"Having H1N1 now would confer immunity in the future -- this seems to be why people born before 1957 have relative immunity," said Horovitz.

What to do About Swine Flu

Dr. John Treanor, a professor of medicine in the infectious diseases unit of the University of Rochester Medical Center, agreed.